Reed operated musical instrument



y 6, 1952 c. E. WETZLER 2,595,316

REED-OPERATED MUSICAL INSTRUMENT Filed July 13, 1948 CHARLES E. WETZLERINVENTOR.

Patented May 6, 1952 UNITED STATES PATENT OFFICE REED OPERATED MUSICALINSTRUMENT Charles E. Wetzler, Long Island City, N. Y.

Application July 13, 1948, Serial No. 38,533 2 Claims. (01.84-377)Another object of the invention is a novel and improved harmonica.

For a better understanding of these and other objects and advantages ofthe invention reference is made to the following description andaccompanying drawings forming part of this application.

In the drawings- Fig. 1 is a partially sectional perspective view of areed-operated musical instrument showing, ingeneral, an embodiment ofthe invention;

Fig. 2 is a partial, sectional view of one element showing details ofone embodiment-of the invention;

Fig. 3, A, B, illustrate, in a more diagrammatic way, other embodimentsof the invention.

Fig. 4-is a partially sectional view of another detail of an instrumentembodying the inven tion.

Reed operated musical instruments such as harmonicas and the likegenerally consist of a flat body portion having a series of channelsformed in each side thereof to act as air ducts or chambers for theoperation of the reeds. The reeds are mounted on slotted plates whichare placed on each side of the body portion with each reed in alinementwith one of the cham bers. Although it is customary to construct aharmonica with all of the blow reeds on one side of the body and thedraw reeds on the other, instruments are also made with both blow anddraw reeds mounted on a single plate. In this instance the body part maybe provided with chambers only on one side with individual chamberscommunicating with the blow and draw reeds.

I have found that with the conventional instruments numerous air pocketsexist with the result that substantial turbulence and eddy currents areproduced which materially reduce the efficiency of the instrument, asfor example in instruments having generally rectangular chambers; Inconventional instruments therefore,

because of a relatively low efficiency and-large power loss, largevolumes of air are required for actuation of the reeds. This greatlylimits the loudness range obtainable on the instrument. Under theseconditions the reed is frequently forced or overdriven by the air sothat instead of operating at its resonant frequency it operates at someslightly lower frequency with a substantial increase in harmoniccontent. The note thus produced sounds fiat and the increased harmoniccontent gives the note a distorted and strained tone. Moreover, withtheconventional instrument musical accompaniment is difiicult be.- cause ofthe sluggish response and lack of sensitivity of the instrument tochanges in air pressure. The player rapidly becomes fatigued because ofthe large volumes of air required and as a result proper interpretationof the music can not be attained.

With my novel and improved chamber construction I have been able tosubstantially eliminate all air pockets and their attendant power lossesand provide a streamlined path for the air to and from the reeds thusmatching the physical dimensions of the chamber aerodynamically with thecharacteristics of the particular reed served by that chamber. In thisway the air economy is greatly improved since it is possible to operatethe instrument with very much smaller volumes of air and withconsiderably improved tonal quality and materially increased loudnessrange. I have attained an improved operation by increasing the velocityof the air stream, in the case of a blow reed for instance, from themouth of the chamber to the reed with the result that a substantiallyuniform direct stream of air impinges on and actuates the reed at itsnormal resonant frequency. The amplitude can then be readily variedthroughout a relatively wide range without overdriving the reed andmodifying the fundamental frequency or normal harmonic content of thenote.

Moreover, by reason of the increase in efliciency of the instrument Ihave found that it responds almost instantly to very slight airpressures.

As previously mentioned, musical instruments of this type are formedwith a plurality of single open ended chambers for the draw and blowreeds. In conventional practice as I know it, the chambers aresubstantially rectangular in" cross section with one of the side wallsformed by the reed plate so that a vibrating reed constitutes part ofthe chamber wall. The player then either blows or draws on the open endof the chamber, depending on whether the reed is of the blow or drawtype, to actuate and vibrate the reed to produce a musical tone.

Fig. 2 illustrates one of my novel and improved chambers formed in theharmonica body Hi. It is provided with tapered side walls l2. In thisway air entering the open end of the chamber at a substantially constantpressure, as obtained for instance by the blowing of a player, willincrease in velocity during its travel through the tapered part l2. Thehigh velocity air then strikes or impinges on the blow reed l8 andcauses it to vibrate. This increased air velocity causes the reed torespond more rapidly-and easily, enabling the player to more accuratelycontrol the amplitude of oscillation of the reed with a correspondinimprovement in tonal quality by avoidance of overdriving or forcing thereed by larger volumes of air.

In some instances, especially where short chambers are used as in thecase of the higher frequency reeds, itmay be desirable to have arelatively large change in area from one end of the chamber to theother.

In Fig. 2 both the side walls l2 and the bottom l3 are tapered towardthe closed end M of the chamber so that the cross-sectional areadecreases uniformly from the open to the closed end. In Figs-3A and 3Bthe area of the chamber throughout its length varies at a predeterminedrate of change.

Fig. 3A illustrates a harmonica body part 453 having a chamber 50 inwhich both the walls 5! and the bottom 57! converge inwardly from themouth at a constantly increasing rate so that the acceleration of theair will be progressively increased as it proceeds through the-chamber.In Fig. 3B I have again shown the body part 40 of a harmonica havingcurved walls 53 and a curved bottom. part 54. In this embodiment,however, the walls and bottom part have a convex configuration so thatthe rate of acceleration of the air is greatest at the mouth anddecreases as it proceeds through the chamber.

Inthe construction of my harmonica it may be desirable to usecombinations of two or more of the new and improved chambers I haveillustratedin Figs. 2 and 3 so that the resultant instrument willrequire substantially uniform air pressure for the reproduction of thevarious tones.

For instance, it may be desirable to use a chamber as illustrated inFig. 3B for actuating a very high frequency reed so that a maximum airvelocity can be attained in a relatively short length, whereas it may bedesirable to use a chamber of the character illustrated in Fig. 2 for alower frequency reed which is physically longer than a higher frequencyreed and therefore enables the use of a longer chamber which will permitthe attainment of substantially equivalent air velocities with a smallerdegree of convergence from the mouth of the chamber to the inner endthereof.

For the purpose of clearly disclosing some of the features of thisinvention I have illustrated the chamber in Fig. 3 as havin asubstantially rectangular section. I have found, however, that eddycurrents and turbulence which increase the friction of an air passageand lower the efficiency of the system can be materially reduced in aharmonica chamber by providing chambers having curved sections and Ihave illustrated an embodiment thereof in Figs. 1 and 2 inclusive.

With the embodiments or combinations of the embodiments in Figs. 2 and3. I have found, in

the case of a mouth-operated harmonica, a loudness range from pianissimoto fortissimo can be obtained by the ordinary player not obtainable withconventional harmonicas with which I am familiar. Because of thedecrease in both volume and pressure of air required to start theindividual reeds to vibrate, the player is able to render more accuratecontrol over the applied air pressure and the reeds can be vibrated intheir normal manner to produce a tone of high quality. In conventionalharmonicas Where the power losses are high, the operator or player mustnecessarily produce relatively large volumes of air at high pressure inorder to start the reeds to vibrate, and this conditon results in anactual forcing of the reeds so that instead of oscillating attheir trueresonant frequencies, will oscillate at difierent fundamentalfrequencies and produce a large distorted harmonica content. Theresultant tone appears to the ear to be out of pitch and the severalreeds when forced in this Way go out of pitch non-uniformly.

My invention permits a wide variation in musical interpretation andexploitation not otherwise feasible and enables the employment of fastertempos in harmonica music,

In addition to the new and improved chamber designs described in Figs. 2and 3, still further improvements in operation can be attained bymountin the reed relative to the chamber so that the resistance to theair flow will be relatively low in comparison to the reactan-ce of thereed. In other words, by the elimination of unnecessary air pocketsbetween the reed and the chamber it is possible to substantially raisethe Q of the reed so that the power required to sustain oscillation issubstantially decreased. In Fig. 4 I have illustrated an embodiment ofthis feature in connection with a draw reed of a mouth operatedharmonica.

Referring toFig. i, "it represents a harmonica body having a chamber "Htherein of the type illustrated in Fig. 2 wherein the bottom wall 12tapers upwardly toward the rear end of the chamber. Closing the top ofthe chamber H is the reed plate 74 having a reed 75 mounted on the platel4 and adapted to vibrate within a slot it. The direction of vibrationof the reed is illustrated by the arrow (2 and the extent of suchvibration in a downward direction is indicated-by the broken outline ofthe reed.

I have been able to further improve the eniciency of harmonicas byproportioning the chamber relative to the reed so that air pockets aresubstantially eliminated. This greatly decreases turbulence and eddycurrents that in effect reduce the Q or the efficiency of theinstrument. I have accomplished this by terminating the chamber II at apoint in front of the inner end of the reed slot It and making theclearance ll between the reed I5 and the upper face Bl of the body 18just large enough to accommodate the swing of the reed [5 when it isvibrated. With this structure I am able to obtain a maximum conversionof the energy of the moving column of air into sound energy.

. In Fig. 4 I have illustrated a chamber H in the body part it! havingconverging walls l3;

In Fig. 2 I have illustrated m new and improved method of improving theQ or the efficiency of a system having a musical reed such as a blowreed in a mouth-operated harmonica having upper and lower sections.

In Fig. 2 I have denoted the body part of the harmonica by the numeralID having upper and lower chambers II and II a. For the purposes of thisdescription I have illustrated but a single reed plate I 5 having a blowreed I8 mounted therein for vibration within the slot I6. Inconventional practice as I know it, the inner wall II, of the chamber IIis usually terminated at a point beyond the free end of the reed I8 sothat the air pocket would be formed between the rear end of the chamberand the upper plate, I5. Moreover, in conventional practice the chambersare made substantially rectangular in cross-section and the relativelysharp corners produced additional eddy currents and other losses. Withmy invention I terminate the rear wall I! of the chamber I Isubstantially in line with the end of the slot I6 so that all of the airentering the mouth of the chamber will be directed upwardly at the reedand be converted into sound energy. Moreover, the particular chamber IIis provided with a curved rear wall II to provide a smooth path for theair.

Referring to Fig. 1 showing a single plate harmonica embodying myinvention, IIO denotes the harmonica body having a reed plate H2 and areed plate cover H4. The body part III} is provided with a plurality ofblow reed chambers I I6 and interposed draw reed chambers II8. Theseblow and draw reed chambers embody the new and improved designs which Ihave illustrated in Figs. 2 to 4 inclusive. Each successive pair of blowand draw reed chambers H6 and H8 respectively is arranged to terminatein a single opening or chamber mouth I since in the operation of theharmonica draw and blow reeds are obviously not operated simultaneously.The reed plate isconstructed to conform with the chambers in the body IIII; that is, the blow reeds I22 and the draw reeds I24 are mountedalternately to cooperate with their respective chambers in the body H0.The cover plate H4 in this particular embodiment is generallystreamlined and tapering inwardl toward the reeds.

In certain instances my new and improved harmonica may be provided withchambers having a curved rear wall substantially as illustrated at I 4in Fig. 2. This feature obviously may be embodied in any of the improvedchambers shown. Moreover, although I have shown individual upper andlower chambers for two plate harmonicas certain advantages of myinvention may also be realized b using a single chamber for opposingupper and lower reeds. In this instance, the side and end walls of thechambers are shaped according to the invention and the chambers arecompleted by closing one side of the chamber with a plate having a drawreed mounted thereon and closing the other side of the chamber with ablow reed mounted thereon.

From the foregoing description of my invention it is clear that a reedoperated musical instrument embodying my invention provides in effect acomplete streamlined path for the air from the point of entrance to thepoint of exit from the chambers. By reducing turbulence in the airstream and the elimination of air pockets to produce the smooth flow ofthe air through the chambers, the ease of operation and rapidity ofresponse of the instrument are improved. The tonal quality is alsoimproved and the range of loudness and tempos are substantiallyincreased. Moreover, by means of tapering the chambers, as I havedescribed, I can materially increase the Velocity of the air strikingthe reed and obtain a more efiicient conversion of air pressure to soundenergy and more uniform operation of the instrument over the entiretonal range. Moreover, I have found that instruments constructed inaccordance with my invention will stay in tune for a longer period oftime because, among other reasons, the reeds are not forced but are freeto vibrate in their natural periods. The overall response of theinstrument is more uniform, sensitive, and easily controlled. All theseand other advantages combine to greatly improve the rendition of musicalcompositions.

I claim:

l. A reed operated musical instrument, comprising a body having pairs ofcoordinated blow and draw chambers open at its front, reeds mounted eachin a slot to swing therein and to cooperate with one of said chambers,the reed associated with a blow chamber mounted with its free end towardthe rear of the body and the reed associated with a draw chamber mountedwith its free end toward the front of the body, the blow chamber of eachpair being longer than the draw chamber, said chambers tapering in crosssection inwardly from the front edge so as to cause a variation of airvelocity in the particular chamber and a maximum velocity substantiallyat the swinging free end of the particular reed, the length and thevariation of cross section of each individual chamber beingaerodynamically matched with the characteristics of the particular reedserved by the respective chamber.

2. A reed operated musical instrument as specified in claim 1, thevariation of cross section in an individual chamber being not uniformalong its length, the rate of variation being aerodynamically matchedwith the characteristics of the particular reed associated with therespective chamber.

CHARLES E. WE'IZLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 59,027 Ingalls Oct. 23, 1866173,652 Lightsinger Feb. 15, 1876 592,850 Weiss Nov. 2, 1897 611,237Curtis Sept. 2'7, 1898 653,451 Hohner July 10, 1900 1,009,904 HohnerNov. 28, 1911' 2,000,408 Minevitch May '7, 1935 2,232,238 Jacomini Feb.18, 1941 2,340,333 Magnus Feb. 1, 1944 FOREIGN PATENTS Number CountryDate 530,803 Great Britain Dec. 20, 1940 399,194 Germany July 28, 1924352,163 Germany of 1922

